1. Field of the Invention
The present invention relates to a music reproducing apparatus.
2. Description of the Related Art
A music reproducing program that allows a smartphone or a tablet PC to function as a music reproducing apparatus is present. The mainstream of audio data to be reproduced by the music reproducing apparatus is PCM data that is encoded by a PCM (Pulse Code Modulation) system in which a sampling frequency is 44.1 kHz and the number of quantum bits is 16 bits. In recent years, there have been DSD data that is encoded by a 1-bit DSD (Direct Stream Digital) system in which a sampling frequency is 2.8224 MHz (=44.1 kHz×64) as audio data. However, since a lot of smartphones that function as the music reproducing apparatus cannot directly reproduce DSD data, the music reproducing program occasionally allows the smartphones to convert DSD data into PCM data and reproduce the PCM data. The DSD data is converted into the PCM data by a low-pass filter process for converting DSD data into multi-bit PCM data of high sampling frequency (2.8224 MHz), and a thinning process for thinning out the multi-bit PCM data of high sampling frequency into PCM data of low sampling frequency (44.1 kHz). In the low-pass filter process, a buffer is generated for data delay.
JP 2007-179604 A discloses an apparatus for performing gapless reproduction for reproducing two audio data sequentially and seamlessly so that a soundless portion is not generated between an audio caused by the audio data to be reproduced formerly and an audio caused by the audio data to be reproduced latterly. Further, JP 9-282800 A discloses an apparatus for performing cross-fade reproduction for reproducing two audio data while performing fade-out and fade-in so that while an audio of the audio data to be reproduced formerly is being faded out, an audio of the audio data to be reproduced latterly is faded in.
In smartphones that cannot reproduce the above DSD data, DSD data should be converted into PCM data also in the gapless reproduction and the cross-fade reproduction. When the gapless reproduction is performed, a conventional music reproducing program generates a new buffer at the time of converting the audio data to be reproduced latterly separately from the buffer generated at the time of converting the audio data to be reproduced formerly. For this reason, a noise is generated between the audio of the audio data to be reproduced formerly and the audio of the audio data to be reproduced latterly at the time of the gapless reproduction.